CN109149616B - Decoupling method and system in ultra/extra-high voltage direct current real-time simulation converter station - Google Patents
Decoupling method and system in ultra/extra-high voltage direct current real-time simulation converter station Download PDFInfo
- Publication number
- CN109149616B CN109149616B CN201810969427.0A CN201810969427A CN109149616B CN 109149616 B CN109149616 B CN 109149616B CN 201810969427 A CN201810969427 A CN 201810969427A CN 109149616 B CN109149616 B CN 109149616B
- Authority
- CN
- China
- Prior art keywords
- pole
- direct current
- converter
- decoupling
- bus
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/36—Arrangements for transfer of electric power between ac networks via a high-tension dc link
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Inverter Devices (AREA)
Abstract
The invention discloses an ultra/extra-high voltage direct current real-time simulation convertor station internal decoupling method and system, and belongs to the technical field of large power grid safety simulation analysis. The method specifically comprises the following steps: determining a decoupling topological structure for decoupling by adopting a plurality of decoupling units between a bipolar direct current converter unit and an alternating current field and a direct current field in a converter station of a high-voltage direct current transmission system; determining a circuit structure of a decoupling element in a decoupling unit in the converter station according to a substitution theorem; determining the circuit structures of the stabilizing elements for decoupling units between the bipolar direct current converting unit and the alternating current field and between the bipolar direct current converting unit and the direct current field respectively; step four, determining a parameter range for a stable element between the bipolar direct current conversion unit and the direct current field pole bus; the invention realizes the decoupling between the bipolar direct current conversion unit and the alternating current field and the direct current field, so that the ultra/extra-high voltage direct current transmission system can realize the small-step electromagnetic transient real-time simulation.
Description
Technical Field
The invention relates to the technical field of large power grid safety simulation analysis, in particular to an ultra/extra-high voltage direct current real-time simulation convertor station internal decoupling method.
Background
With the rapid development and progress of economic society in China, energy safety, climate change and sustainable development become important strategic problems of economic society development in China. In order to adapt to the development of the economic society, in recent years, the rapid development of the extra-high voltage power grid is continuously promoted by national power grid companies, and extra-high voltage direct current becomes one of the main technical means for supporting the construction of the extra-high voltage power grid.
After a large amount of extra/extra-high voltage direct currents are connected into a power grid, novel power grid patterns such as alternating current and direct current parallel operation, receiving end direct current multi-feed-in and the like are formed, and the operation and response characteristics of a direct current transmission system can bring great influence on the operation characteristics of an alternating current and direct current series-parallel power grid. In order to provide technical support for planning, construction and operation of a large number of ultra/extra-high voltage direct current engineering access power grids, a reliable and effective simulation means is required.
The digital-analog hybrid simulation technology of the actual direct current protection device is adopted, and the method is a reliable technical means for accurately simulating the alternating current-direct current hybrid power grid. The most key technology of the digital-analog hybrid simulation is to realize the real-time simulation of a power grid and realize the connection with a physical direct-current protection device. In general, the smaller the simulation step size, the higher the real-time simulation precision, but the higher the real-time requirement. Therefore, the simulation of the alternating current power grid is realized by adopting a digital-analog hybrid simulation mode, and the real-time performance of the simulation model of the ultra/extra-high voltage direct current power transmission system under a small step length is realized firstly.
The basic means for realizing the real-time implementation is model decoupling, namely, a larger calculation model is divided into a plurality of small models capable of performing parallel calculation through corresponding technical means, and then the real-time implementation is realized through the parallel calculation of the super server. The smaller the simulation step size, the higher the decoupling difficulty. The common decoupling method is decoupling through a long transmission line, and the decoupling method has the advantages of no decoupling distortion and good stability after decoupling, and has the defects that the decoupling can only be carried out at a transmission line with a certain length, and the decoupling mode is inflexible.
For an ultra/extra-high voltage direct current transmission system, two converter stations can be naturally decoupled through a direct current transmission line, but because the transmission line does not exist in the converter stations, the decoupling is a technical problem. However, for small-step real-time simulation, the decoupling between the converter stations is difficult to meet the actual application requirements, and a practical decoupling scheme in the converter stations must be explored.
Disclosure of Invention
The invention aims to realize the small-step real-time simulation of the ultra/extra-high voltage direct current, improve the real-time simulation precision of a power system while realizing the connection with a physical simulation device, is suitable for the digital-analog mixed real-time simulation research of an alternating current-direct current power grid, and provides an intra-ultra/extra-high voltage direct current real-time simulation convertor station decoupling method, which specifically comprises the following steps: determining decoupling topological structures for decoupling by adopting decoupling units between a bipolar direct current converter unit and an alternating current field and between the bipolar direct current converter unit and a direct current field in a converter station of the ultra/extra-high voltage direct current transmission system;
the bipolar direct current converter unit includes: a pole I converter unit and a pole II converter unit;
determining the circuit structures of decoupling elements in decoupling units between a bipolar direct current converter unit and an alternating current field and between the bipolar direct current converter unit and the direct current field in the converter station according to a substitution theorem;
determining the circuit structures of the stable elements for decoupling units between the bipolar direct current converter unit and the alternating current field and between the bipolar direct current converter unit and the direct current field in the converter station respectively;
step four, determining a parameter range for a stable element between the bipolar direct current conversion unit and the direct current field;
optionally, the alternating current field comprises a stabilizing element and a current converting bus; the pole I commutation cell comprises: an extreme I converter flow and converter valve; the pole II commutation cell comprises: a pole II converter transformer and converter valve; the direct current field includes: the circuit comprises a stabilizing element, a polar I direct current filter, a polar II direct current filter, a polar I bus, a polar II bus, a polar I neutral bus, a polar II neutral bus, a polar I impact capacitor and a polar II impact capacitor;
the pole I converter valve is connected with the secondary side of the pole I converter transformer, and the pole II converter valve is connected with the secondary side of the pole II converter transformer;
the stable element in the alternating current field is connected with a commutation bus, decoupling elements are arranged between the commutation bus in the alternating current field and a pole I commutation transformer and a pole II commutation transformer in a bipolar direct current commutation unit respectively, and the decoupling elements and the stable element connected with the commutation bus in the alternating current field form an alternating current field decoupling unit;
the direct current field is characterized in that a stable element is connected with a pole I bus and a pole II bus, an impact capacitor is connected with a pole I neutral bus and a pole II neutral bus, a decoupling element is arranged between the pole I neutral bus and the pole I bus in the direct current field and a converter valve in a pole I converter unit, a decoupling element is arranged between the pole II bus and the pole II neutral bus in the direct current field and a converter valve in the pole II converter unit, the stable element and the decoupling element form a group of decoupling units, and the impact capacitor and the decoupling element form a group of decoupling units;
optionally, the decoupling element in the converter station is represented as an I side and a V side, the I side and the V side are respectively connected with a circuit outside the decoupling element, a circuit connected with the V side of the decoupling element is represented as a current source on the I side, a current value flowing into the V side is taken as a current source value, a circuit connected with the I side of the decoupling element is represented as a voltage source on the V side, and a voltage value is taken as a voltage to ground of a bus on the I side;
optionally, the stabilizing element comprises: a stable capacitor and a reactive compensation load are added at the I side of a decoupling element between the bipolar direct current conversion unit and the alternating current field; damping resistance and stable capacitance are added at the side I of the decoupling element between the bipolar direct current conversion unit pole bus and the direct current field; the impact capacitance at the neutral bus utilized by the decoupling element between the neutral bus of the bipolar direct current conversion unit and the direct current field;
optionally, the parameter range is that the value range of the effective stable capacitance is between 0.1uF and 0.5uF, and the value range of the damping resistance is in the order of hundred ohms.
Optionally, the converter stations include a double-twelve pulse structure direct current converter station, a single-twelve pulse structure direct current converter station, a double-twelve pulse structure multi-terminal direct current converter station, and a double-twelve pulse structure layered access direct current converter station.
Optionally, the alternating current field includes N stabilizing elements and N sets of commutation buses, and one set of commutation buses connects one stabilizing element and N decoupling elements, where N is greater than or equal to 1.
Optionally, the impact capacitor in the dc field is used as a stabilizing element for connecting the neutral bus of the pole I and the neutral bus of the pole II.
Optionally, the alternating current power supply further comprises an alternating current filter in the alternating current field, a pole I direct current filter, a pole II direct current filter and a grounding electrode in the direct current field, the alternating current filter and the pole I converter transformer and the pole II converter transformer are connected to the converter bus on the primary side, and the grounding electrode is connected between the pole I neutral bus and the pole II neutral bus.
Optionally, the converter also comprises a pole I smoothing reactor and a pole II smoothing reactor, wherein the pole I smoothing reactor is connected between the pole I converter valve and the stabilizing element, and the pole II smoothing reactor is connected between the pole II converter valve and the stabilizing element.
The invention also provides an ultra/extra-high voltage direct current real-time simulation convertor station internal decoupling system, which is characterized in that: the method comprises a topology determining unit, a decoupling topology structure and a decoupling topology structure, wherein the decoupling topology structure is used for decoupling by adopting a decoupling unit between a bipolar direct current converter unit and an alternating current field and between the bipolar direct current converter unit and a direct current field in a converter station of the ultra/extra-high voltage direct current transmission system;
the bipolar direct current converter unit includes: a pole I converter unit and a pole II converter unit;
the decoupling element determining unit is used for determining the circuit structures of decoupling elements in the decoupling units between the bipolar direct current converter unit and the alternating current field and between the bipolar direct current converter unit and the direct current field in the converter station according to a substitution theorem;
the stable element determining unit is used for determining the circuit structures of the stable elements respectively for decoupling units between the bipolar direct current converter unit and the alternating current field and between the bipolar direct current converter unit and the direct current field in the converter station;
the parameter determining unit is used for determining a parameter range for a stable element between the bipolar direct current converting unit and the direct current field;
the alternating current field comprises a stabilizing element and a current conversion bus; the pole I commutation cell comprises: an extreme I converter flow and converter valve; the pole II commutation cell comprises: a pole II converter transformer and converter valve; the direct current field includes: the circuit comprises a stabilizing element, a polar I direct current filter, a polar II direct current filter, a polar I bus, a polar II bus, a polar I neutral bus, a polar II neutral bus, a polar I impact capacitor and a polar II impact capacitor;
the pole I converter valve is connected with the pole I converter transformer secondary side, and the pole II converter valve is connected with the pole II converter transformer secondary side;
the decoupling element and the stabilizing element connected with the commutation bus in the alternating current field form an alternating current field decoupling unit;
the direct current field is characterized in that a stabilizing element is connected with a pole I bus and a pole II bus, an impact capacitor is connected with a pole I neutral bus and a pole II neutral bus, a decoupling element is arranged between the pole I neutral bus and the pole I bus in the direct current field and a converter valve in a pole I converter unit, a decoupling element is arranged between the pole II bus and the pole II neutral bus in the direct current field and a converter valve in the pole II converter unit, the stabilizing element and the decoupling element form a group of decoupling units, and the impact capacitor and the decoupling element form a group of decoupling units;
the decoupling element in the converter station is characterized in that the decoupling element is represented as an I side and a V side, the I side and the V side are respectively connected with a circuit outside the decoupling element, the circuit connected with the V side of the decoupling element is represented as a current source on the I side, the numerical value of the current source is the current value flowing into the V side, the circuit connected with the I side of the decoupling element is represented as a voltage source on the V side, and the numerical value of the voltage source is the voltage to ground of a bus on the I side;
the stabilizing element comprises: a stable capacitor and a reactive compensation load are added at the I side of a decoupling element between the bipolar direct current conversion unit and the alternating current field; damping resistance and stable capacitance are added at the side I of the decoupling element between the bipolar direct current conversion unit pole bus and the direct current field; the impact capacitance at the neutral bus utilized by the decoupling element between the neutral bus of the bipolar direct current conversion unit and the direct current field;
the parameter range of the stabilizing element between the bipolar direct current converting unit and the direct current field pole bus determines that the value range of the effective stabilizing capacitance is between 0.1uF and 0.5uF, and the value range of the damping resistance is in the order of hundred ohms.
Optionally, the converter stations include a double-twelve pulse structure direct current converter station, a single-twelve pulse structure direct current converter station, a double-twelve pulse structure multi-terminal direct current converter station, and a double-twelve pulse structure layered access direct current converter station.
Optionally, the alternating current field includes N stabilizing elements and N sets of commutation buses, and one set of commutation buses connects one stabilizing element and N decoupling elements, where N is greater than or equal to 1.
Optionally, the impact capacitor in the dc field is used as a stabilizing element for connecting the neutral bus of the pole I and the neutral bus of the pole II.
Optionally, the alternating current power supply further comprises an alternating current filter in the alternating current field, a pole I direct current filter, a pole II direct current filter and a grounding electrode in the direct current field, the alternating current filter and the pole I converter transformer and the pole II converter transformer are connected to the converter bus on the primary side, and the grounding electrode is connected between the pole I neutral bus and the pole II neutral bus.
Optionally, the converter also comprises a pole I smoothing reactor and a pole II smoothing reactor, wherein the pole I smoothing reactor is connected between the pole I converter valve and the stabilizing element, and the pole II smoothing reactor is connected between the pole II converter valve and the stabilizing element.
The invention realizes the decoupling between the bipolar direct current converter unit and the alternating current field and between the bipolar direct current converter unit and the direct current field, and the decoupling topological structure in the converter station is determined by the implementation of the invention, and the decoupling topological structure comprises the following components: the system comprises an alternating current field, a pole I (for layered access or high-end) converter unit, a pole II (for layered access or low-end) converter unit and a direct current field, wherein each converter station can have four tasks to be processed in parallel, so that the workload of each parallel computing task is greatly reduced, and the small-step electromagnetic transient real-time simulation of the ultra/extra-high voltage direct current transmission system becomes possible.
Drawings
FIG. 1 is a flow chart of a decoupling method in an ultra/extra-high voltage direct current real-time simulation converter station according to the invention;
FIG. 2 is a diagram of a decoupling topology structure in an extra/extra-high voltage direct current real-time simulation converter station of a double-twelve-pulse structure decoupling method in an extra-high voltage direct current converter station of the present invention;
FIG. 3 is a circuit diagram of a decoupling element based on a substitution theorem of the decoupling method in the ultra/extra-high voltage direct current real-time simulation converter station according to the invention;
FIG. 4 is a decoupling element interface timing sequence based on a substitution theorem of the decoupling method in the ultra/extra-high voltage direct current real-time simulation converter station according to the invention;
FIG. 5 is a circuit diagram of an alternating current field decoupling unit of the decoupling method in the ultra/extra-high voltage direct current real-time simulation converter station;
FIG. 6 is a circuit diagram of a direct current field decoupling unit of the decoupling method in the ultra/extra-high voltage direct current real-time simulation converter station according to the invention;
FIG. 7 is a structural diagram of a decoupling system in an ultra/extra-high voltage direct current real-time simulation converter station.
Detailed Description
The exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, however, the present invention may be embodied in many different forms and is not limited to the embodiments described herein, which are provided for complete and complete disclosure of the present invention and to fully convey the scope of the present invention to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the accompanying drawings is not intended to be limiting of the invention. In the drawings, the same units/elements are denoted by the same reference numerals.
Unless otherwise defined, terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Further, it will be understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense.
FIG. 1 is a flow chart of a decoupling method in an ultra/extra-high voltage direct current real-time simulation converter station according to the invention; an ultra/extra-high voltage direct current real-time simulation converter station internal decoupling method specifically comprises the following steps as shown in fig. 1:
determining decoupling topological structures for decoupling by adopting decoupling units between a bipolar direct current converter unit and an alternating current field and between the bipolar direct current converter unit and a direct current field in a converter station of the ultra/extra-high voltage direct current transmission system; wherein the bipolar DC converter unit comprises: a pole I converter unit and a pole II converter unit;
fig. 2 is a diagram of a decoupling topology structure in an extra/extra-high voltage direct current real-time simulation converter station according to a twenty-two pulse structure decoupling method in the extra/high voltage direct current real-time simulation converter station, as shown in fig. 2, wherein the decoupling topology structure in the converter station includes: the alternating current field comprises a stabilizing element and a current conversion bus; the pole I commutation cell comprises: an extreme I converter flow and converter valve; the pole II commutation cell comprises: a pole II converter transformer and converter valve; the direct current field includes: the circuit comprises a stabilizing element, a polar I direct current filter, a polar II direct current filter, a polar I bus, a polar II bus, a polar I neutral bus, a polar II neutral bus, a polar I impact capacitor and a polar II impact capacitor;
wherein the pole I converter valve is connected with the secondary side of the pole I converter transformer, and the pole II converter valve is connected with the secondary side of the pole II converter transformer;
the decoupling element and the stabilizing element connected with the commutation bus in the alternating current field form an alternating current field decoupling unit; the alternating current field comprises N stabilizing elements and N groups of commutation buses, one group of commutation buses is connected with one stabilizing element and N decoupling elements, wherein N is larger than or equal to 1.
The direct current field is connected with a pole I bus and a pole II bus, the impact capacitor in the direct current field is connected with a pole I neutral bus and a pole II neutral bus, and the impact capacitor in the direct current field is used as a stabilizing element for connecting the pole I neutral bus and the pole II neutral bus;
in the direct current field, a decoupling element is arranged between a pole I neutral bus and a pole I bus and a converter valve in a pole I converter unit, a decoupling element is arranged between a pole II bus and a pole II neutral bus and a converter valve in a pole II converter unit, a group of decoupling units is formed by the stabilizing element and the decoupling element, and a group of decoupling units is formed by the impact capacitor and the decoupling element;
the invention also comprises an alternating current filter in the alternating current field, a pole I direct current filter, a pole II direct current filter and a grounding electrode in the direct current field, wherein the alternating current filter and the pole I converter transformer and the pole II converter transformer primary side are connected to the converter bus, and the grounding electrode is connected between the pole I neutral bus and the pole II neutral bus.
The converter also comprises a pole I smoothing reactor and a pole II smoothing reactor, wherein the pole I smoothing reactor is connected between the pole I converter valve and the stabilizing element, and the pole II smoothing reactor is connected between the pole II converter valve and the stabilizing element.
The invention realizes the complete decoupling between the converter unit and the direct current field, between the converter unit and the alternating current field, and between the pole I converter unit and the pole II converter unit, and realizes the decoupling in the direct current converter station.
Step two: determining the circuit structures of decoupling elements in decoupling units between a bipolar direct current converter unit and an alternating current field and between the bipolar direct current converter unit and the direct current field in a converter station according to a substitution theorem; FIG. 3 is a decoupling element structure based on a substitution theorem of the decoupling method in the ultra/extra-high voltage direct current real-time simulation converter station according to the invention; as shown in fig. 3, the decoupling element is represented as two parts, I side and V side, the two sides are respectively connected with the circuit outside the decoupling element, the circuit connected with the V side of the decoupling element is represented as a current source on the I side inside the decoupling element, and the value of the current source is the value of the current flowing into the V side; and representing a circuit connected with the I side part of the decoupling element as a voltage source on the V side, wherein the voltage source value is the voltage to ground of the I side bus to realize decoupling.
Step three: determining the circuit structures of the stabilizing elements respectively for decoupling units between a bipolar direct current converting unit and an alternating current field and between the bipolar direct current converting unit and the direct current field in the converter station; the decoupling topological structure of the invention needs to operate without error, and must strictly meet the requirements of substitution theorem: the value of the I-side current source and the value of the V-side voltage source at each moment should be consistent with the injection current of the V-side and the node voltage of the I-side respectively, but the condition cannot be achieved in practice due to the discrete calculation characteristic of a digital simulation program. Supposing that the simulation result of the voltage of the node at the I side is U (T) at the time T, theoretically, the voltage source output at the V side needs to be instantaneously adjusted to be U (T) at the time, but actually, the simulation result at the other side of the decoupling element cannot be obtained in real time in the real-time simulation process, and only the simulation result at the previous time step, namely U (T-T), is obtained, wherein T is the simulation step length; for the current source value on the I side as well, only the current I (T-T) of one time step on the V side can be acquired at time T. Wherein the interface timing is as shown in FIG. 4; the decoupling element according to the substitution theorem naturally has a delay error of a simulation step length during real-time simulation, and an interface causes instability of a simulation system during real-time simulation. Through simulation experiments, the instability of the decoupling interface is generally shown as self-oscillation of a high-frequency signal, and the self-oscillation can be inhibited by adding a capacitor on the current source side (I side). The stabilizing element on the alternating current side is shown in fig. 5, the stabilizing capacitor is a main element for realizing interface stabilization, and the stabilizing capacitor is added on the side I of the decoupling element realized based on the substitution theorem, so that instability caused by delay errors can be effectively inhibited; meanwhile, because the addition of the stabilizing capacitor brings errors to the reactive power flow of the system, a reactive compensation load is added to the side I of the decoupling element and is used for compensating the reactive errors brought by the addition of the stabilizing capacitor. Through practical application, for an ultra/extra-high voltage direct current transmission system, stable decoupling of a current conversion unit and an alternating current field can be realized only by adding a group of stable loops on a current conversion bus, and simulation precision can be ensured.
As shown in fig. 2, an impact capacitor generally exists at the neutral bus of the dc field, and the impact capacitor can be naturally used as a stabilizing element, and the impact capacitor at the neutral bus is directly used as the stabilizing capacitor, so that no additional stabilizing element needs to be added in the neutral bus decoupling interface of the commutation unit and the dc field. For a bipolar direct current converter unit and a polar bus decoupling interface of a direct current field, the invention designs a direct current field decoupling unit as shown in fig. 6.
As shown in fig. 6, the stabilizing loop is formed by a rc loop, wherein the capacitor is used to stabilize the oscillation of the decoupling loop, and the resistor is used to damp the charging and discharging processes of the capacitor during the transient process of the dc field. The decoupling unit at the polar line of the direct current field realized by the method effectively inhibits high-frequency oscillation brought by the decoupling element, realizes stable operation of an ultra/extra-high voltage direct current system, and simultaneously avoids negative effects brought by charging and discharging response of a stable capacitor in a transient process on a direct current control protection system by the design of a damping resistor.
And step four, designing stable element parameters in the direct current field decoupling unit. In order to reduce the change degree of the parameters of the main loop of the ultra/extra-high voltage direct current transmission system, avoid influencing various transient/steady-state response characteristics of direct current, and simultaneously have the capability of inhibiting high-frequency oscillation, the value range of the effective stable capacitance finally determined by matching with the damping resistance is between 0.1uF and 0.5uF, and the value range of the damping resistance is in the order of hundred ohms.
In addition, the ultra/extra-high voltage direct current transmission project mainly comprises a double-twelve pulse structure extra-high voltage direct current converter station, a single-twelve pulse structure direct current converter station, a double-twelve pulse structure multi-terminal/layered access direct current converter station and other forms, and the converter station internal structures are different.
FIG. 7 is a structural diagram of an internal decoupling system of an ultra/extra-high voltage direct current real-time simulation converter station according to the present invention
The invention also provides a decoupling system in the ultra/extra-high voltage direct current real-time simulation converter station, which comprises a topology determining unit and a decoupling topology structure, wherein the topology determining unit is used for determining the decoupling topology structure for decoupling by adopting a decoupling unit between a bipolar direct current converter unit and an alternating current field and between the bipolar direct current converter unit and a direct current field in the converter station of the ultra/extra-high voltage direct current transmission system; the converter stations comprise a double-twelve pulse structure direct current converter station, a single-twelve pulse structure direct current converter station, a double-twelve pulse structure multi-terminal direct current converter station and a double-twelve pulse structure layered access direct current converter station.
Wherein, bipolar direct current commutation unit includes: a pole I converter unit and a pole II converter unit;
the decoupling element determining unit is used for determining the circuit structures of decoupling elements in the decoupling units between the bipolar direct current converter unit and the alternating current field and between the bipolar direct current converter unit and the direct current field in the converter station according to a substitution theorem;
the stable element determining unit is used for determining the circuit structures of the stable elements respectively for decoupling units between the bipolar direct current converter unit and the alternating current field and between the bipolar direct current converter unit and the direct current field in the converter station;
the parameter determining unit is used for determining a parameter range for a stable element between the bipolar direct current converting unit and the direct current field;
the alternating current field comprises a stabilizing element and a current conversion bus; the pole I commutation cell comprises: an extreme I converter flow and converter valve; the pole II commutation cell comprises: a pole II converter transformer and converter valve; the direct current field includes: the circuit comprises a stabilizing element, a polar I direct current filter, a polar II direct current filter, a polar I bus, a polar II bus, a polar I neutral bus, a polar II neutral bus, a polar I impact capacitor and a polar II impact capacitor;
the pole I converter valve is connected with the pole I converter transformer secondary side, and the pole II converter valve is connected with the pole II converter transformer secondary side;
the decoupling element and the stabilizing element connected with the commutation bus in the alternating current field form an alternating current field decoupling unit; the alternating current field comprises N stabilizing elements and N groups of commutation buses, wherein one group of commutation buses is connected with one stabilizing element and N decoupling elements, and N is greater than or equal to 1.
The direct current field is connected with a polar I bus and a polar II bus, the impact capacitor in the direct current field is connected with a polar I neutral bus and a polar II neutral bus, and the impact capacitor in the direct current field is used as a stabilizing element for connecting the polar I neutral bus and the polar II neutral bus.
In the direct current field, a decoupling element is arranged between a pole I neutral bus and a pole I bus and a converter valve in a pole I converter unit, a decoupling element is arranged between a pole II bus and a pole II neutral bus and a converter valve in a pole II converter unit, a group of decoupling units is formed by the stabilizing element and the decoupling element, and a group of decoupling units is formed by the impact capacitor and the decoupling element;
the invention also comprises an alternating current filter in the alternating current field, a pole I direct current filter in the direct current field, a pole II direct current filter and a grounding electrode, wherein the alternating current filter and the pole I converter transformer and the pole II converter transformer primary side are connected to the converter bus, and the grounding electrode is connected between the pole I neutral bus and the pole II neutral bus. The converter also comprises a pole I smoothing reactor and a pole II smoothing reactor, wherein the pole I smoothing reactor is connected between the pole I converter valve and the stabilizing element, and the pole II smoothing reactor is connected between the pole II converter valve and the stabilizing element.
The decoupling element in the converter station is represented as an I side and a V side, the I side and the V side are respectively connected with a circuit outside the decoupling element, the circuit connected with the V side of the decoupling element is represented as a current source on the I side, the numerical value of the current source is the current value flowing into the V side, the circuit connected with the I side of the decoupling element is represented as a voltage source on the V side, and the numerical value of the voltage source is the voltage to ground of a bus on the I side;
wherein the stabilizing element comprises: a stable capacitor and a reactive compensation load are added at the I side of a decoupling element between the bipolar direct current conversion unit and the alternating current field; damping resistance and stable capacitance are added at the side I of the decoupling element between the bipolar direct current conversion unit pole bus and the direct current field; the impact capacitance at the neutral bus utilized by the decoupling element between the neutral bus of the bipolar direct current conversion unit and the direct current field;
the parameter range of the stabilizing element between the bipolar direct current converting unit and the direct current field pole bus determines that the value range of the effective stabilizing capacitance is between 0.1uF and 0.5uF, and the value range of the damping resistance is in the order of hundred ohms.
The decoupling topology structure in the converter station as shown in fig. 2 determined by the invention realizes the complete decoupling of the converter unit of the bipolar direct current converter unit and the alternating current field as well as the bipolar direct current converter unit and the direct current field, and the invention has universality to various direct current transmission systems: when the connection relation between the alternating current field or the direct current field and the bipolar converter unit is changed, the interface element and the stabilizing element provided by the invention exist at each interface of the alternating current field or the direct current field and the bipolar direct current converter unit, and the ultra/extra-high voltage direct current converter station can be decoupled. For a direct current transmission system with other intra-station topological structures, which is not listed in the invention, the method can be applied to realize complete decoupling of the converter unit and the alternating current field and complete decoupling of the converter unit and the direct current field, and the method has the same essence.
Claims (10)
1. An ultra/extra-high voltage direct current real-time simulation convertor station internal decoupling method is characterized by comprising the following steps: comprises the steps of (a) preparing a mixture of a plurality of raw materials,
determining decoupling topological structures for decoupling by adopting decoupling units between a bipolar direct current converter unit and an alternating current field and between the bipolar direct current converter unit and a direct current field in a converter station of the ultra/extra-high voltage direct current transmission system;
the bipolar direct current converter unit includes: a pole I converter unit and a pole II converter unit;
determining the circuit structures of decoupling elements in decoupling units between a bipolar direct current converter unit and an alternating current field and between the bipolar direct current converter unit and the direct current field in the converter station according to a substitution theorem;
determining the circuit structure of the stabilizing element according to decoupling units between the bipolar direct current converting unit and the alternating current field and between the bipolar direct current converting unit and the direct current field in the converter station;
step four, determining a parameter range for a stable element between the bipolar direct current conversion unit and the direct current field;
the alternating current field comprises a stabilizing element and a current conversion bus; the pole I commutation cell comprises: a pole I converter flow and a pole I converter valve; the pole II commutation cell comprises: a pole II converter flow and a pole II converter valve; the direct current field includes: the circuit comprises a stabilizing element, a polar I bus, a polar II bus, a polar I neutral bus, a polar II neutral bus, a polar I impact capacitor and a polar II impact capacitor;
the pole I converter valve is connected with the pole I converter transformer secondary side, and the pole II converter valve is connected with the pole II converter transformer secondary side;
the decoupling element and the stabilizing element connected with the commutation bus in the alternating current field form an alternating current field decoupling unit;
the direct current field is characterized in that a stabilizing element is connected with a pole I bus and a pole II bus, a pole I impact capacitor and a pole I neutral bus in the direct current field are connected, a pole II impact capacitor and a pole II neutral bus are connected, a decoupling element is arranged between the pole I neutral bus and a converter valve in a pole I converter unit in the direct current field, and a decoupling element is arranged between the pole I bus and the converter valve in the pole I converter unit; a decoupling element is arranged between the pole II bus and the converter valve in the pole II converter unit, a decoupling element is arranged between the neutral bus of the pole II and the converter valve in the pole II converter unit, the decoupling element connected with the stable element in the direct current field and the pole bus forms a group of decoupling units, and the impact capacitor in the direct current field and the decoupling element connected with the neutral bus form a group of decoupling units;
the decoupling element is represented as an I side and a V side, the I side and the V side are respectively connected with a circuit outside the decoupling element, the circuit connected with the V side of the decoupling element is represented as a current source on the I side, the numerical value of the current source is the value of current flowing into the V side, the circuit connected with the I side part of the decoupling element is represented as a voltage source on the V side, and the numerical value of the voltage source is the voltage to ground of a bus on the I side;
the stabilizing element comprises: a stable capacitor connected with a commutation bus at the I side of a decoupling element between the bipolar direct current commutation unit and the alternating current field and a reactive compensation load of the commutation bus; the damping resistance and the stable capacitance of the I pole bus of the connecting pole at the I side of the decoupling element between the bipolar direct current conversion unit pole bus and the direct current field and the damping resistance and the stable capacitance of the II pole bus of the connecting pole are connected; the impact capacitance of the neutral bus of the connecting pole I and the impact capacitance of the neutral bus of the connecting pole II are connected on the side I of the decoupling element between the neutral bus of the bipolar direct current conversion unit and the direct current field;
the parameter range is that the value range of the stable capacitance is between 0.1uF and 0.5uF, and the value range of the damping resistance is in the order of hundred ohms.
2. The method of claim 1, wherein: the converter stations comprise a double-twelve pulse structure direct current converter station, a single-twelve pulse structure direct current converter station, a double-twelve pulse structure multi-terminal direct current converter station and a double-twelve pulse structure layered access direct current converter station.
3. The method of claim 1, wherein: the alternating current field comprises N stabilizing elements and N groups of commutation buses, wherein one group of commutation buses is connected with one stabilizing element and M decoupling elements, and M is larger than or equal to 1.
4. The method of claim 1, wherein: the alternating current filter and the pole I converter transformer and the pole II converter transformer are connected to the converter bus on the primary side, and the grounding electrode is connected between the pole I neutral bus and the pole II neutral bus.
5. The method of claim 1, wherein: the bipolar direct current converter unit further comprises a pole I smoothing reactor and a pole II smoothing reactor between the bipolar direct current converter unit and the direct current field, the pole I smoothing reactor is connected between the pole I converter valve and the stabilizing element, and the pole II smoothing reactor is connected between the pole II converter valve and the stabilizing element.
6. The utility model provides an interior decoupling system of super/extra-high voltage direct current real-time simulation converter station which characterized in that includes:
the topology determining unit is used for determining a decoupling topology structure which is decoupled by adopting a decoupling unit between a bipolar direct current converting unit and an alternating current field and between the bipolar direct current converting unit and a direct current field in a converter station of the ultra/extra-high voltage direct current transmission system;
the bipolar direct current converter unit includes: a pole I converter unit and a pole II converter unit;
the decoupling element determining unit is used for determining the circuit structure of the decoupling element according to decoupling units between the bipolar direct current converter unit and the alternating current field and between the bipolar direct current converter unit and the direct current field in the converter station according to a substitution theorem;
the stable element determining unit is used for determining the stable element according to the circuit structures of the stable elements in the decoupling units between the bipolar direct current converter unit and the alternating current field and between the bipolar direct current converter unit and the direct current field in the converter station respectively;
the parameter determining unit is used for determining a parameter range for a stable element between the bipolar direct current converting unit and the direct current field;
the alternating current field comprises a stabilizing element and a current conversion bus; the pole I commutation cell comprises: a pole I converter flow and a pole I converter valve; the pole II commutation cell comprises: a pole II converter flow and a pole II converter valve; the direct current field includes: the circuit comprises a stabilizing element, a polar I direct current filter, a polar II direct current filter, a polar I bus, a polar II bus, a polar I neutral bus, a polar II neutral bus, a polar I impact capacitor and a polar II impact capacitor;
the pole I converter valve is connected with the pole I converter transformer secondary side, and the pole II converter valve is connected with the pole II converter transformer secondary side;
the decoupling element and the stabilizing element connected with the commutation bus in the alternating current field form an alternating current field decoupling unit;
the direct current field is characterized in that a stabilizing element is connected with a pole I bus and a pole II bus, a pole I impact capacitor and a pole I neutral bus in the direct current field are connected, a pole II impact capacitor and a pole II neutral bus are connected, a decoupling element is arranged between the pole I neutral bus and a converter valve in a pole I converter unit in the direct current field, and a decoupling element is arranged between the pole I bus and the converter valve in the pole I converter unit; a decoupling element is arranged between the pole II bus and the converter valve in the pole II converter unit, a decoupling element is arranged between the neutral bus of the pole II and the converter valve in the pole II converter unit, the decoupling element connected with the stable element in the direct current field and the pole bus forms a group of decoupling units, and the impact capacitor in the direct current field and the decoupling element connected with the neutral bus form a group of decoupling units;
the decoupling element is represented as an I side and a V side, the I side and the V side are respectively connected with a circuit outside the decoupling element, the circuit connected with the V side of the decoupling element is represented as a current source on the I side, the current source value is a current value flowing into the V side, the circuit connected with the I side part of the decoupling element is represented as a voltage source on the V side, and the voltage source value is a voltage to ground voltage of a bus on the I side;
the stabilizing element comprises: a stable capacitor connected with a commutation bus at the I side of a decoupling element between the bipolar direct current commutation unit and the alternating current field and a reactive compensation load of the commutation bus; the damping resistance and the stable capacitance of the I pole bus of the connecting pole at the I side of the decoupling element between the bipolar direct current conversion unit pole bus and the direct current field and the damping resistance and the stable capacitance of the II pole bus of the connecting pole are connected; the impact capacitance of the neutral bus of the connecting pole I and the impact capacitance of the neutral bus of the connecting pole II are connected on the side I of the decoupling element between the neutral bus of the bipolar direct current conversion unit and the direct current field;
the parameter range of the stabilizing element between the bipolar direct current conversion unit and the direct current field pole bus is that the value range of the stabilizing capacitance is between 0.1uF and 0.5uF, and the value range of the damping resistance is in the order of hundred ohms.
7. The system of claim 6, wherein: the converter stations comprise a double-twelve pulse structure direct current converter station, a single-twelve pulse structure direct current converter station, a double-twelve pulse structure multi-terminal direct current converter station and a double-twelve pulse structure layered access direct current converter station.
8. The system of claim 6, wherein: the alternating current field comprises N stabilizing elements and N groups of commutation buses, wherein one group of commutation buses is connected with one stabilizing element and M decoupling elements, and M is larger than or equal to 1.
9. The system of claim 6, wherein: the alternating current filter and the pole I converter transformer and the pole II converter transformer are connected to the converter bus on the primary side, and the grounding electrode is connected between the pole I neutral bus and the pole II neutral bus.
10. The system of claim 6, wherein: the bipolar direct current converter unit further comprises a pole I smoothing reactor and a pole II smoothing reactor between the bipolar direct current converter unit and the direct current field, the pole I smoothing reactor is connected between the pole I converter valve and the stabilizing element, and the pole II smoothing reactor is connected between the pole II converter valve and the stabilizing element.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810969427.0A CN109149616B (en) | 2018-08-23 | 2018-08-23 | Decoupling method and system in ultra/extra-high voltage direct current real-time simulation converter station |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810969427.0A CN109149616B (en) | 2018-08-23 | 2018-08-23 | Decoupling method and system in ultra/extra-high voltage direct current real-time simulation converter station |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109149616A CN109149616A (en) | 2019-01-04 |
| CN109149616B true CN109149616B (en) | 2021-10-12 |
Family
ID=64827653
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810969427.0A Active CN109149616B (en) | 2018-08-23 | 2018-08-23 | Decoupling method and system in ultra/extra-high voltage direct current real-time simulation converter station |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109149616B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102157929A (en) * | 2011-04-13 | 2011-08-17 | 国网电力科学研究院 | Main wiring method of multi-terminal ultra high voltage direct current transmission system |
| CN104866665A (en) * | 2015-05-19 | 2015-08-26 | 清华大学 | Hybrid simulation method including power electronic equipment based on interface equivalence and interaction |
| WO2017023391A3 (en) * | 2015-05-13 | 2017-04-06 | Raytheon Company | System and method for parallel configuration of hybrid energy storage module |
| US9893633B1 (en) * | 2016-03-23 | 2018-02-13 | The Florida State University Research Foundation, Inc. | Modular multilevel DC-DC converter and associated method of use |
| CN108181835A (en) * | 2017-12-30 | 2018-06-19 | 贵州大学 | A kind of electric system DC grid real-time emulation method and device |
-
2018
- 2018-08-23 CN CN201810969427.0A patent/CN109149616B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102157929A (en) * | 2011-04-13 | 2011-08-17 | 国网电力科学研究院 | Main wiring method of multi-terminal ultra high voltage direct current transmission system |
| WO2017023391A3 (en) * | 2015-05-13 | 2017-04-06 | Raytheon Company | System and method for parallel configuration of hybrid energy storage module |
| CN104866665A (en) * | 2015-05-19 | 2015-08-26 | 清华大学 | Hybrid simulation method including power electronic equipment based on interface equivalence and interaction |
| US9893633B1 (en) * | 2016-03-23 | 2018-02-13 | The Florida State University Research Foundation, Inc. | Modular multilevel DC-DC converter and associated method of use |
| CN108181835A (en) * | 2017-12-30 | 2018-06-19 | 贵州大学 | A kind of electric system DC grid real-time emulation method and device |
Non-Patent Citations (2)
| Title |
|---|
| Advanced Hybrid Transient Stability and EMT Simulation for VSC-HVDC Systems;A. A. van der Meer;《IEEE Transactions on Power Delivery》;20141222;全文 * |
| 高压直流输电系统数字物理动态仿真;周俊 等;《电工技术学报》;20120526;全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109149616A (en) | 2019-01-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Beerten et al. | Generalized steady-state VSC MTDC model for sequential AC/DC power flow algorithms | |
| CN108336751B (en) | Electromechanical transient modeling method for LCC-MMC hybrid direct-current power grid | |
| CN110198044B (en) | LCC-HVDC commutation failure immunity evaluation method and system considering transmission power limit | |
| CN103825478A (en) | Control method of modular multilevel converter based on power frequency fixed switching frequency | |
| CN109617112B (en) | Improved direct-current voltage control strategy applicable to multi-terminal flexible direct-current system | |
| CN112255567B (en) | Short-circuit current rapid determination method for power distribution network containing photovoltaic power supply | |
| Maalla | Research on Reactive Power Control of the HVDC Transmission System | |
| Kong et al. | Phase-locked strategy of photovoltaic connected to distribution network with high proportion electric arc furnace | |
| CN109149616B (en) | Decoupling method and system in ultra/extra-high voltage direct current real-time simulation converter station | |
| CN103618322B (en) | Dynamic reactive efficiency quantitative evaluation method oriented towards transient voltage stability | |
| CN105896558B (en) | VSC-based UPFC electromechanical transient modular modeling method | |
| CN105071397A (en) | Coordinated reactive voltage control method of different reactive compensation devices of wind power delivery | |
| CN110442042B (en) | Digital physical hybrid real-time simulation system for electric vehicle to be connected with power electronic transformer | |
| CN204333972U (en) | Multi-end flexible direct current transmission equipment | |
| US20220366115A1 (en) | General decoupling method and system for electromagnetic transient simulation of voltage source converter | |
| CN106301038A (en) | The control circuit of a kind of Switching Power Supply fixed frequency and control method | |
| CN105305392A (en) | Symmetrical component method for short circuit calculation of voltage-controlled type IIDG included power distribution network | |
| CN111898282B (en) | Improved modularized multi-level converter Thevenin equivalent modeling method | |
| CN110968973B (en) | Simulation method, control method, electronic equipment and storage medium of transformer model | |
| CN109560561B (en) | Dynamic simulation method, system and storage medium for three-phase asymmetric operation of active power distribution network | |
| CN108667008B (en) | Universal small signal modeling method for subsynchronous oscillation analysis of power system | |
| Wang et al. | Effects of DC power flow controller on DC power network loss | |
| CN110957737A (en) | Five-terminal power injection modeling method for 500kV unified power flow controller | |
| CN103400309A (en) | Method for evaluating influence of ultrahigh-voltage access on stability of provincial power grid | |
| CN115933443B (en) | Fan modeling method based on joint inspection of RT-LAB hardware in loop and PSASP |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |